The present invention relates to a folding former for a web-fed rotary newspaper press, the folding former including a former nose and a pivot point or a pivot axis, the folding former being pivotable about the pivot point or the pivot axis to horizontally displace the former nose which changes a former inclination angle (β), a former spread angle (γ) being changeable as a function of the former inclination angle (β).
The present invention also relates to a method for producing a printed product, such as a newspaper, having a plurality of sections, each section being provided with a longitudinal fold in a different folding former.
Folders of presses are used to form folds on printed printing materials. In prior art devices, a web-like printing material is first led through what is known as a folding former to form a longitudinal fold on the web-like and not yet severed printing material. Starting from the folding former, the web-like printing material is transported over a plurality of pull rolls in the direction of a cutting knife cylinder and a folding blade cylinder interacting with the cutting knife cylinder, copies being divided off from the web like printing material on the cutting knife cylinder and being moved in the direction of a folding jaw cylinder with the aid of the folding blade cylinder. The copy divided off from the web-like printing material on the cutting knife cylinder, which copy is moved in the direction of the folding jaw cylinder by the folding blade cylinder, is transferred from the folding blade cylinder to the folding jaw cylinder, forming a cross fold. The present invention relates to folding formers for the formation of the longitudinal folds on web-like and not yet severed printing material.
U.S. Pat. No. 5,016,863 discloses a folding former of a web-fed rotary press having two former halves. The folding former has a folder nose and a centre of gravity, it being possible for the folding former to be pivoted about the centre, of gravity, changing a former inclination angle, in order to displace the former nose horizontally forwards and/or backwards. U.S. Pat. No. 5,016,863 also discloses the practice of changing the former flank angle of the two former halves, depending on the change in the former inclination angle. The sum of the two former flank angles determines what is known as the former spread angle of the folding former.
During the production of printed products, in particular newspapers, having a plurality of sections, it is usual for sections of different thicknesses to be provided with appropriate longitudinal folds simultaneously on a plurality of folding formers. If a plurality of sections of different thickness are combined to font a printed product, for example a newspaper, then the position of an outer edge of the respective section is determined by the thickness of the same, the outer edges of thicker sections lying further forward than the outer edges of thinner sections. For visual reasons, however, it is desirable to bring the outer edges of all the sections into the same position in the finished product. Only then is there a visually ideally folded printed copy. Until now, the prior art has disclosed no folding formers which take account of this phenomenon.